The invention relates to a process and apparatus for the separate release of a closure in a motor vehicle with a central locking system, wherein a central control circuit of the central locking system is activatable from a locking station assigned to the individual closure at least for its direct release and to effect indirect release or locking of further closures through release or locking control signals generated during the actuation of this locking station in a releasing or a locking direction through an electrical switch means coupled to this locking station
A process with these general features can be derived from the influencing of a central locking system (hereafter referred to as CLS) according to German Offenlegungsschrift 3,612,306.
There, an electrical switch in the passenger space of the vehicle can be activated electrically in the blocking direction by a solenoid valve inserted in a dual-pressure line leading to a line distributor. The blocking solenoid valve prevents actuating elements, connected to the line distributor via fluid lines, from being subjected to a releasing pressure. At any time, it is possible to subject those actuating elements assigned to the closures of the passenger and rear doors, to a locking vacuum via a non-return valve connected in parallel with the solenoid valve With the solenoid valve closed, i.e. with the electrical switch closed and the magnet winding live, only the driver-door closure is released in response to a corresponding actuation of its lock cylinder. The remaining closures remain locked because the actuating elements assigned to them cannot be subjected to pressure, even though a CLS control signal is generated by a control switch assigned to the driver-door closure.
German Offenlegungsschrift 2,931,136 provides electrical switches arranged in the passenger space of a vehicle that can only be cancelled during release, or during release and locking, so that only an individual release or individual locking of all the closures is possible.
These two systems are inconvenient in that the electrical switches allowing the individual release of a particular closure can be actuated only from the interior. The vehicle user therefore has to decide, before leaving the vehicle, whether next time he gets in, he wishes to or has to release all the closures centrally, or only the driver-door closure.
The object of the invention is to develop a CLS in such a way that a choice between a central release of all the closures or only a direct release of one closure from the same locking station can be made, each time the vehicle is unlocked from outside, and to provide at least one central locking system which is suitable for carrying out this process.
In the CLS having a central control circuit the central locking system is activatable from a locking station assigned to the individual closure at least for its direct release and to effect indirect release, or locking of further closures, through release or locking control signals generated during the actuation of this locking station in a releasing or a locking direction through an electrical switch means coupled to this locking station. This object is achieved when the locking station is actuated once in the releasing direction by having only the associated closure directly released and no release control signal is generated for the other closures. When the locking station is actuated several times within a predetermined time interval, the central control circuit is activated in the releasing direction to release all of the closures.
A central locking system having a central control circuit for the operation of closure actuating elements both in a releasing and a locking direction for carrying out the above process comprises a central control circuit, which is activatable at least indirectly by locking and release control signals at the one locking station assigned to the drivers closure, at least for its direct release through a first switch means coupled to this locking station As a result of the actuation of the switch in a releasing or locking direction an electrical potential is connected to a control line for operating the closure actuating elements. A second switch means is coupled to the locking station and switched at least whenever the latter is actuated in a releasing direction. A pulse counter is connected to the second switch means and a logic module is connected to the pulse counter, and is inserted in a control line between the first switch means and the central control circuit. The pulse counter transmits an output signal activating the logic module for the transmission of a release control signal to the central control circuit via the control line only in response to a number of switch signals of the second switch means and only if the signals are generated within a time interval predetermined by the said pulse counter. The logic module transmits a locking control signal (with a polarity opposite the polarity of the release control signal) to the central control circuit via the control line as early as a response to a switch signal of the first switch means is generated, when the locking station is actuated once in a locking direction.
Another structure for carrying out the process has the central control circuit activatable at least indirectly by locking or release control signals (at the one locking station assigned to a specific closure) via a switch means coupled to this locking station and co-actuated during each actuation of the locking station in both a releasing and a locking direction. The switch, via a respective control line, can be subjected to an electrical potential according to the direction of actuation of the switch means for operation of the closure actuating elements. Here the switch is coupled to the locking station and to the pulse counter, provided in a control line subjected to an electrical potential, when the locking station or the switch means is actuated in the releasing direction. The pulse counter counts switch signals of the switch means occurring in the control line and transmits a release control signal to the central control circuit via the control line only in response to a number of switch signals of the switch means, if generated within a time interval predetermined in the said pulse counter.
The invention makes use of the fact that the closure assigned directly to a particular locking station, formed by a mechanical lock cylinder, can always be released and locked mechanically from this locking station. The set object is achieved because a CLS control signal is generated in the releasing direction only when this locking station is actuated several times, even though the switch means provided for this station are switched during each actuation of the locking station.
It is known (German Patent Specification 3,113,893 and German Offenlegungsschrift 3,136,468) to prevent needless energy consumption by switching on an electrical door-lock heating unit only when the door-lock outer handle (pull handle, push button, etc.) is actuated twice within a predetermined time interval. These publications do not give information on a procedure according to the invention for the influencing of a CLS.
It is advantageous if the predetermined time interval is defined by the first generation of the switch signal and if the switch signals are detected and counted by a counting device inserted between the switch means generating them and the central control circuit. Additionally, the counting device after reaching a predetermined number of switch signals will generate the release control signal at least indirectly. Also, the counting device is reset to an initial state both after the expiration of the predetermined time interval and also upon generation of a locking control signal from a switch actuated during the time interval in a locking direction and during the actuation of the locking station.
Control principles are known from German Offenlegungsschrift 3,612,306 and from German Patent Specification 3,531,349. They differ from one another purely outwardly in the number of electrical control lines leading from the switch means in the locking stations to the particular central control circuit. In the first German patent there are two lines which, depending on the direction of actuation of the switch means, that can be subjected alternately to a constant electrical potential and are potential-free in the state of rest. In the second German specification, only one control line leads from each locking-station switch means to the central control circuit, and this control line can be subjected alternately to a positive and negative electrical potential. The second-mentioned German Patent Specification also discloses second switch means which are assigned to the particular locking station and whenever this is actuated by a master key, the locks are co-actuated and play an important part in the CLS. Nevertheless, no information on a function according to the instant invention of the CLS can be found even in the second-mentioned German Patent Specification.
In Applicant's device it is advantageous if there is a timing circuit which is triggerable by the first switch signal of the switch means, which is connected to the pulse counter via a counting input, and which presets the time interval in the pulse counter. Also advantageous is the fact that the pulse counter has a reset input connected to the switch means and switchable by the locking station during the actuation of the latter in the locking direction. Here, when the locking station is actuated in the locking direction, the pulse counter is reset to an initial state. Also after the expiration of the time interval, the timing circuit generates a signal resetting the pulse counter to an initial state.